Assay Development
Assay system components
The enzyme-linked immunosorbent assay (ELISA) is one of the most widely used techniques in both basic immunology research and diagnostic analyses. Because ELISA enables peptides, proteins, antibodies, and hormones to be selectively detected in small concentrations among a multitude of other substances with relatively low cost and high simplicity, the method provides an important and useful tool for disease monitoring, diagnostics, doping tests, and environmental and food analytics. ELISA...
Introduction to Biochemical and Chemical Reagents
IVD kits and assays are dependent upon several different biochemical and chemical reagents working together to produce an accurate and specific result with proven reliability at the lowest possible cost. Adaptability to an automated format and consistency among tests produced are also key requirements. Typical biochemical and chemical assay reagents include antibodies, an essential element for conferring specificity to immunoassays; buffers and media, which provide an optimal environment to...
A kidney injury biomarker initiative
Evidence has been accumulating that several novel biomarkers will become powerful clinical tools for detecting treatment-induced acute kidney injury (AKI) and diagnosing impaired kidney function.1 In 2004, FDA launched the Critical Path Initiative (CPI) with the purpose of improving drug development.2 In order to support CPI, the Critical Path Institute, an independent non-profit institute, was developed in 2005 to facilitate collaboration among FDA scientists, academia, and industry for the...
Immobilized Trypsin
Immobilized Trypsin is TPCK-treated trypsin immobilized on 4% agarose. It helps to eliminate contamination of protein digests by the enzyme and is readily removed by separating the agarose from the digestion solution. The TPCK treatment inactivates the interfering chymotrypsin activity. A serine endopeptidase, trypsin cleaves peptide bonds on the carboxy side of s-aminoethyl cysteine, arginine, and lysine residues. After trypsin digestion, the peptides are readily identified by mass...
Reading Alpha Assays
Further expanding the Synergy microplate reader family, the Synergy 2 Alpha microplate reader provides high-performance Alpha detection for low- to medium-throughput laboratories. Synergy 2 Alpha comes preconfigured with the Alpha filter set, mirrors, software, and optical modules to read all Alpha assays, and it is upgradable with additional detection modes as the laboratory’s needs change. Synergy 2 Alpha’s sensitivity is on par with that of laser-based systems, the manufacturer...
Exploring FDA-Approved IVDMIAs
The sequencing of the human genome in 2001 brought about rapid development of technologies to measure multiple genes, which resulted in the creation of gene arrays. These tests, and multianalyte protein marker panels, constitute a new type of advanced diagnostic that is rapidly entering the clinical laboratory.1 As a result of the vast information that was made available from the Human Genome Project, great expectations developed that we would be able to diagnose, target, predict, and treat a...
Enrichment and Mass Spectrometry
A phosphopeptide enrichment kit aids in processing protein digests and strong cation exchange fractions to selectively recover phosphopeptides for mass spectrometric analysis in less than 30 minutes. The Pierce Fe-NTA Phosphopeptide Enrichment Kit supplies high-capacity Fe-NTA spin columns and optimized buffer for analyzing 30 protein digests. The phosphopeptide-specific resin in each spin column will sufficiently enrich up to 150 micrograms of phosphopeptides. The spin columns complement other...
Adapting the lateral-flow immunoassay format for detecting enzyme activity
The lateral-flow immunochromatographic assay (LFIA) format has achieved considerable commercial success, as demonstrated by strong sales of pregnancy and drugs-of-abuse tests.1-4 Because of its simplicity, low cost, and user-friendliness, LFIA is particularly attractive for point-of-care and over-the-counter tests. Although LFIA has been primarily used for qualitative detection, several new technologies capable of generating quantitative measurements have emerged. Such technologies include...
Cepheid earns WHO endorsement of rapid TB test
Cepheid’s Xpert MTB/RIF test won the endorsement of the World Health Organization (WHO) last December. The test has the potential to revolutionize TB care and treatment by accurately diagnosing patients in about 100 minutes—a huge reduction in time to results compared to conventional TB diagnosis, a WHO representative said in a press statement. Cepheid (Sunnyvale, CA) is offering a 75% discount on the price of the test and the table-top computer system that goes with it to...
The Coulter Principle and the development of IVDs
The Coulter Principle provides a method for counting and sizing cells, and its proper application has contributed to advances in IVDs. The principle can be applied to every stage of test development, from studies of basic cellular biology, through preclinical physiological testing, and ultimately in routine clinical diagnostics. With a better understanding of the Coulter Principle and its contributions, IVD manufacturers may find new ways of applying the technique to their own IVD tests. ...